The present invention relates to a portable circuit identifier. In recent years there has been a virtual explosion in the market for integrated circuit electronics, both analog and digital. In many applications where high precision and tolerance of extreme environmental conditions are required, hybrid integrated circuits and various standard modules are also popular.
Today there are hundreds of standard integrated circuits available, all of which fit in one of several standard socket configurations. The most widely known configuration is a standard dual-in-line (DIP) socket for circuits having between four and sixteen pins. More recently, twenty-four, forty, and sixty-four pin dual-in-line configurations having wider spacing between the rows of sockets have become popular in the field of large scale integrated circuits (LSI). Additionally, SEM and SEEM standard modules are commonly used in military equipment. As greater and greater circuit density has been obtained in the field of integrated circuits, together with the ability to fabricate circuits on relatively large chips, the field of large scale integrated circuits has provided extremely complex functions available in standard integrated circuit (IC) packages.
The proliferation of the use of intregrated circuits in consumer products has created a need for a portable testing device for complex integrated circuits. A novel, very efficient portable integrated circuit tester constructed of hardware similar to the preferred embodiment of the present invention is shown in applicant's co-pending application Ser. No. 96,030, now U.S. Pat. No. 4,291,404, filed Nov. 20, 1979 entitled "AUTOMATIC CIRCUIT TESTER WITH IMPROVED VOLTAGE REGULATOR". The invention disclosed herein is related in that the preferred embodiments are physically constructed according to FIG. 3 herein. Furthermore, there are common aspects of the interconnections used in the invention of said co-pending application and the present invention. Therefore, said co-pending application Ser. No. 96,030 is hereby incorporated by reference exactly as if set forth in full herein.
The apparatus shown in application Ser. No. 96,030 is a device for testing whether a circuit placed in a test socket is properly performing the functions of a particular selected identified circuit. In other words, it is necessary to know the identity of the circuit in order to ascertain whether the circuit is operating properly.
The great increase in use of integrated circuits, and particularly the use of a large number of different circuits housed in identical packages, together with the custom of labeling circuits with "in-house" numbers, has caused serious problems for field service personnel. The nature of one of the problems is basically a simple ignorance of the identity of a particular integrated circuit.
As will be appreciated by those familiar with modern electronic manufacturing customs, many original-equipment manufacterers (OEM) order standard integrated circuits in large quantities with the purchaser's "in-house" part number designated thereon and omit the generic identifier for the device. This custom is used in order to keep the internal part numbering scheme of the OEM purchaser in a form which the purchaser wants, and provides a way to force ultimate consumers to buy spare parts from the OEM.
It will therefore be appreciated that in field service work one often encounters a situation where the only "missing link" in the chain of knowledge necessary to repair a particular item is the generic identity of an integrated circuit labeled with an in-house number.
It is therefore desirable to provide apparatus which can effect the identification of a particular circuit in a standard package.
Furthermore, on many pieces of military equipment, such as a particular airplane or submarine, it is known that only certain types of standard modules are used in the particular piece. It is therefore desirable to provide apparatus which can rapidly test a standard module to determine if its operation corresponds to proper operation of any member of a known set of possible modules.